<?php
class Jssdk {
  private $appId;
  private $appSecret;

  public function __construct($appId, $project_id) {
	 $this->appId ='wxc3926d97e0dbcf4e';
    $this->appSecret ='41650eab872ae4d4ef897deb1434c074';
  }

  public function getSignPackage($url) {
    $jsapiTicket = $this->getJsApiTicket();

    // 注意 URL 一定要动态获取，不能 hardcode.
    $protocol = (!empty($_SERVER['HTTPS']) && $_SERVER['HTTPS'] !== 'off' || $_SERVER['SERVER_PORT'] == 443) ? "https://" : "http://";
    //$url = "$protocol$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";
    //$url = "http://house.new.guanyu.cn/Webrong/index2.html";

    $timestamp = time(); 
    $nonceStr = $this->createNonceStr();
	//echo($timestamp."|".$jsapiTicket."|".$nonceStr."|".$url);
	//echo("alert('".$timestamp."|".$jsapiTicket."|".$nonceStr."|".$url."');");
    // 这里参数的顺序要按照 key 值 ASCII 码升序排序
    $string = "jsapi_ticket=$jsapiTicket&noncestr=$nonceStr&timestamp=$timestamp&url=$url";

    $signature = sha1($string);

    $signPackage = array(
      "appId"     => $this->appId,
      "nonceStr"  => $nonceStr,
      "timestamp" => $timestamp,
      "url"       => $url,
      "signature" => $signature,
      "rawString" => $string
    );
    return $signPackage; 
  }
  
  public function getMediafile($media_id){
    $accessToken = $this->getAccessToken();
	$url = "http://file.api.weixin.qq.com/cgi-bin/media/get?access_token=$accessToken&media_id=$media_id";
	//$res = $this->httpGet($url,1);
	$html = file_get_contents($url);
	return array("res"=>$html,"head"=>self::parseHeaders($http_response_header));
  }
  

  private function createNonceStr($length = 16) {
    $chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
    $str = "";
    for ($i = 0; $i < $length; $i++) {
      $str .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
    }
    return $str;
  }

  private function getJsApiTicket() {
    // jsapi_ticket 应该全局存储与更新，以下代码以写入到文件中做示例
    $data = json_decode(file_get_contents("./access_token/".$this->appId."_jsapi_ticket.json"));
    //$data->expire_time = 0;
    if ($data->expire_time < time()) {
      $accessToken = $this->getAccessToken();

      // 如果是企业号用以下 URL 获取 ticket
      // $url = "https://qyapi.weixin.qq.com/cgi-bin/get_jsapi_ticket?access_token=$accessToken";
      $url = "https://api.weixin.qq.com/cgi-bin/ticket/getticket?type=jsapi&access_token=$accessToken";
      $res = json_decode($this->httpGet($url));
      $ticket = $res->ticket;
      if ($ticket) {
        $data->expire_time = time() + 7000;
        $data->jsapi_ticket = $ticket;
	    file_put_contents("./access_token/".$this->appId."_jsapi_ticket.json",json_encode($data));
        /* $fp = fopen("jsapi_ticket.json", "w");
        fwrite($fp, json_encode($data));
        fclose($fp); */
      }
    } else {
      $ticket = $data->jsapi_ticket;
    }
    return $ticket;
  }

  private function getAccessToken() {
    // access_token 应该全局存储与更新，以下代码以写入到文件中做示例
    $data = json_decode(file_get_contents("./access_token/access_token_".$this->appId.".json"));
	$data->expire_time = 0;
    if ($data->expire_time < time()) {
      // 如果是企业号用以下URL获取access_token
      //$url = "https://qyapi.weixin.qq.com/cgi-bin/gettoken?corpid=$this->appId&corpsecret=$this->appSecret";
      $url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=$this->appId&secret=$this->appSecret";
	  $res = json_decode($this->httpGet($url));
      $access_token = $res->access_token;
      if ($access_token) {
       $data->expire_time = time() + $res->expires_in;
       $data->access_token = $access_token;
	   file_put_contents("./access_token/access_token_".$this->appId.".json",json_encode($data));
       /* $fp = fopen("access_token".$this->appId.".json", "w");
       fwrite($fp, json_encode($data));
       fclose($fp); */
      }
    } else {
     $access_token = $data->access_token;
    }
    return $access_token;
  }

  private function httpGet($url) {
    $curl = curl_init();
	//curl_setopt($curl, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_0);
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($curl, CURLOPT_TIMEOUT, 500);
    // 为保证第三方服务器与微信服务器之间数据传输的安全性，所有微信接口采用https方式调用，必须使用下面2行代码打开ssl安全校验。
    // 如果在部署过程中代码在此处验证失败，请到 http://curl.haxx.se/ca/cacert.pem 下载新的证书判别文件。
    curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, FALSE);
    curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, FALSE);
    curl_setopt($curl, CURLOPT_URL, $url);
	$res = curl_exec($curl);
	curl_close($curl);
	return $res;
  }
  
  function parseHeaders( $headers )
  {
    $head = array();
    foreach( $headers as $k=>$v )
    {
        $t = explode( ':', $v, 2 );
        if( isset( $t[1] ) )
            $head[ trim($t[0]) ] = trim( $t[1] );
        else
        {
            $head[] = $v;
            if( preg_match( "#HTTP/[0-9\.]+\s+([0-9]+)#",$v, $out ) )
                $head['reponse_code'] = intval($out[1]);
        }
    }
    return $head;
  }
}

